Collect statistics for
mysqlnd_qc_get_core_stats()?
Does not influence storage handler statistics! Handler statistics
can be an integral part of the handler internal storage format.
Therefore, collection of some handler statistics cannot be disabled.

If mysqlnd_qc.collect_statistics and
mysqlnd_qc.collect_statistics_log_file
are set, the plugin will dump statistics into the specified
log file at every 10th web request during PHP request shutdown.
The log file needs to be writable by the web server user.

Whether to remove SQL comments from a query string before
hashing it to generate a cache key. Disable if you do not want
two statemts such as SELECT /*my_source_ip=123*/ id FROM test
and SELECT /*my_source_ip=456*/ id FROM test to refer
to the same cache entry.